Adenosine-5{40 -carboxylic acid amides

ABSTRACT

Adenosine-5&#39;&#39;-carboxylic acid amides represented by the formula   WHEREIN R1 and R2 are each selected from the group consisting of hydrogen, loweralkyl, lowerhaloalkyl, lowerhydroxyalkyl, lowercycloalkyl, loweralkylcycloalkyl, loweralkenyl, lowerhaloalkenyl, lowerhydroxyalkenyl, loweralkynyl, lowerhaloalkynyl, benzylamino, phenyl, loweralkylphenyl, loweralkoxyloweralkyl, substituted phenyl, 2-methylfuran or di(C1-C4)alkylamino(C1-C4)alkyl, adamantyl or R1 and R2 taken together form a 5 or 6 membered heterocyclic moiety; R3 and R4 are hydrogen or acyl, or taken together form an isopropylidene or a benzylidene group; or a pharmaceutically acceptable acid addition salt thereof.

United States Patent [191 Stein et al.

[ 1 Feb. 4, 1975 ADENOSlNE-5-CARBOXYLIC ACID AMlDES [75] Inventors: Herman Hal Stein, Skokie, lll.; Raj

Nandan Prasad, Pierrefonds, Quebec, Canada [73] Assignee: Abbott Laboratories, North Chicago, Ill.

[22] Filed: June 14, 1973 [21] Appl. No.: 370,084

Related U.S. Application Data [60] Division of Ser. No. 236,980, March 22, 1972, which is a continuation-in-part of Ser. No. 125,893, March 18, 1971.

52 U.S. Cl. 424/180, 260/211.5 R 51 Int. Cl ..A61k 27/00 58 Field of Search 424/180 [56] References Cited UNITED STATES PATENTS 3,697,504 10/1972 Schmidt ..260/211.5R

Primary Examiner-Shep K. Rose Attorney, Agent, or Firm-Robert L. Niblack; Joyce R. Krei; Vincent A. Mallare [57] ABSTRACT Adenosine-5'-carboxylic acid amides represented by the formula 1 Claim, N0 Drawings continuation-in-part of copending application Ser.' No. 125,893, filed Mar. 18, I971.

DETAILED DESCRIPTION OF THE INVENTION This invention relates to adenosine derivatives and more particularly relates to adenosine-5 carboxylic acid amides, to intermediates useful in their preparation and to methods of using the compounds.

The compounds of this invention are represented by the formula wherein R and R are each selected from the group consisting of hydrogen, Ioweralkyl, Iowerhaloalkyl, lowerhydroxyalkyl, lowercycloalkyl, loweralkylcycloalkyl, loweralkenyl, Iowerhaloalkenyl, Iowerhydroxyalkenyl, loweralkynyl, Iowerhaloalkynyl, benzylamirio, phenyl, loweralkylphenyl, lowcralkoxyloweralkyl, substituted phenyl, Z-methylfuran or di(C,- C,)alkylamino (C,-C,)alkyl, adamantyl or R, and R taken together form a 5 or 6 membered heterocyclic moiety; R and R, are hydrogen or acyl, or taken togather form an isopropylidene or a benzylidene group; or a pharmaceutically acceptable acid addition salt thereof. Compounds wherein R and R are hydrogen are useful in treating cardiovascular disorders and are particularly useful as anti-hypertensive and anti-anginal agents. A number of amides also exhibit antiinflammatory activity.

The term "IoweralkyF as used herein refers to C -C straight and branched chain alkyl groups including methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, tertbutyl, iso-butyl, n-pentyl, iso-pentyl, neo-pentyl, nhexyl, iso-hexyl and the like.

The term *loweralkenyl" refers to alkenyl groups having from 2-6 carbon atoms such as vinyl, allyl, methallyl, l-pentenyl and the like.

The term "Ioweralkynyl refers to C -C4, ,alkynyl groups including ethynyl, propargyl, 2-butynyl, lpentynyl and 2-hexynyl.

The term halo" includes chloro, fluoro, bromo and iodo.

The term lowercycloalkyl refers to C -C cycloalkyl groups and includes cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and cycloheptyl.

The term Ioweralkylcycloalkyl refers to C -C cycloalkylloweralkyl groups such as cyclopropylmethyl and the like.

The term alkoxyloweralkyl refers to alkoxyalkyl groups having a total of no more than 6 carbon atoms such as methoxymethyl, methoxyethyl, cthoxycthyl, propoxypropyl, propoxyethyl and the like.

The term substituted phenyl" refers to a phenyl group substituted in the ortho, meta or para position by a loweralkyl, Ioweralkoxy or halo atom or a disubstituted phenyl group containing two of the above mentioned radicals such as 3,4-dimethoxyphenyl, 3,5- dimethylphenyl, 3-chloro-4-methylphenyl and the like.

The term 5 or 6 membered heterocyclic moiety" includes morpholino, thiomorpholino, piperidino, homopiperidino, piperazino, pyrrolidino and the like.

The term pharmaceutically acceptable acid addition salts refers to salts prepared by reacting the amide with an organic or inorganic acid. Representative salts include hydrochloride, hydrobromide, sulfate. bisulfate, acetate, valerate, oleate, laurate, borate, benzoate, lactate, phosphate, tosylate, citrate, maleate, succinate, tartrate, napsylate and the like.

Representative compounds of this invention include: adenosine-S'-carboxamide; adenosine-5-(N-methyl)- carboxamide; adenosine-S'-(N-iso-propyl)carboxamide; adenosine-S'-(N-ethyI)-carboxamide; adenosine- 5'-(N-n-propyl)carboxamide; adenosine-5-(N-iso-butyl)carboxamide; adenosine-5- (N-n-butyUcarboxamide; adenosine-S'-(N-n-pentyl)- carboxamide; adenosine-S-(N-iso-pentyl)carboxamide; adenosine-S-(N,N-dimethyUcarboxamide; adenosine-5-(N,N-diethyl)carboxamide; adenosine-5'- (N,N-diisopropyl )carboxamide; adenosine-S N- methyl-N-ethyl)carboxamide; adenosine'5-(N- cycIobutyl)-carboxamide; adenosine-5'-(N- cyclopropylmethyl)carboxamide; adenosine-5-(N- propargyl)-carboxamide; adenosine-S-(N-allyl)carboxamide; adenosine-S -(N-ethoxyethyl)carboxamide; adenosine'5-(N,N-dicyclopropylmethyl)carboxamide; adenosine-5-(N,N-dichloroethyl)carboxamide.

The compounds of this invention are useful as blood pressure lowering agents when administered to hypertensive patients in dosages of from 0001-25 mg./kg. of body weight daily. The compounds are also useful in the management and treatment of angina pectoris when administered to patients suffering from or prone to such attacks in dosages of from 0001-25 mg./kg. of body weight daily. In both instances, it is preferred to administer the compounds orally, however, the compounds may also be administered via intravenous administration. The compounds can be administered in single doses, however, it is preferred that they can be administered in divided doses, i.e., 3-4 times daily.

In addition to their cardiovascular activity, a number of amides exhibit anti-inflammatory activity at dosages of 0.04 to mg./kg. of body weight, with a number of the compounds having an ED in the rat paw edema test of under I mg./kg.

The compounds of this invention can be prepared by converting adenosine-5'-carboxylic acid (prepared from 2',3-isopropylidene adenosine according to the method described by Harmon et al, Chem. Ind. I969, I l4l to the corresponding acid chloride by reacting it with thionyl chloride and then reacting the acid chloride with ammonia or an appropriately substituted alkyl amine such as methylamine. dimethylamine and the like. It will be obvious to those skilled in the art that other well-known procedures can also be employed to prepare the compounds of this invention.

The 2',3-hydroxyl groups of the starting acid can be temporarily blocked by using the protective groups which are conventional in sugar chemistry. The protecting groups can be acyl groups, preferably acetyl or benzoyl groups, or ketals, such as the 2,3' isopropylidene or benzylidene, which can be converted back to the 2',3'-dihydroxy compounds by methods well-known in the art, preferably after the conversion of the acid chloride to the amide. The 2,3- isopropylidene adenosine starting material is-commercially available from Pfanstiehl Corporation, North Chicago, Illinois and the preparation thereof is well known. A number of the intermediates also exhibit cardiovascular activity.

The preferred synthetic route is represented by the following reaction'scheme:

poured, in a thin stream, onto a large volume of well stirred dry ether. The yellow precipitate of 2.3'- isopropylidene adenosine-5-carboxylic acid chloride. m.p. l90l95 dec. was filtereed and washed with an excess of dry ether. This material was used directly for the preparation ofthe amides without any further puri fication.

EXAMPLE 2 Adenosine-5'-Carboxamide A mixture of 6.8 of 2',3'-isopropylidene adenosine- 5-carboxylic acid chloride and ml. of liquid anhydrous ammonia was stirred for two (2) hours at 60 to 50C. At the end -of this time the ammonia was allowed to evaporate off at room temperature. The residue was triturated with cold aqueous sodium bicarbonate solution (lN). The resulting insoluble solid was filtered, washed with cold water and recrystallized from ethanol to yield 3.5 g. of crude 2,3- isopropylidene adenosine-5'-carboxamide, m.p. 220222. The amide was then mixed with lOO ml. of l N hydrochloric acid and maintained at a temperature l i N o l ll noc l soc1 me l o O I 0 CH3 \CH3 2 u N a u u R 0 ll a+ R2 or 0H 1 cu; cu

The following examples further illustrate the present 55 invention:

EXAMPLE I 2,3-lsopropylidene Adenosine-5-Carboxylic Acid Chloride 2',3-lsopropylidene adenosine-5-carboxylic acid (12.8 g.) [prepared according to the method of R. E. Harmon, et al, Chem. Ind. London, N0. 33, i141 (1969)] was added to an excess of thionyl chloride (70 ml.) at 0C. The mixture was stirred for l hour at 0C. and then the temperature was allowed to go up to room temperature for another hour. The clear solution was EXAMPLE 3 Adenosine-S N-methyl )Carboxamide 2,3'-lsopropylidene adenosine-5-[N-methylcarboxamide] (m.p. 264-265) was prepared according to the method of Example 2 from 2,3-isopropylidene adenosine-5-carboxylic acid chloride and an excess of dry liquid methylamine at to l0C. The 2Z3" isopropylidene group was cleaved by the use of 1N HCl at 60 for 45 minutes to give adenosine-5'-(N-methyl)- carboxamide in 44% yield; m.p. 240-24l; [01],, 23: 0.6 (C, 3.2 in 1H HCl). Elemental analysis and nuclear magnetic resonance data con firmed the identity of the compound.

EXAMPLE 4 Adenosine-5-(N,N-dimethyl)Carboxamide l3.5 g. of 2,3-isopropylidene adenosine-5'- carboxylic acid chloride was stirred with excess dry dimethylamine at -l0 to 0C. The clear solution was allowed to warm to room temperature. In about 3 hours the unreacted dimethylamine had evaporated off. The residue was washed with ether and dissolved in the minimum amount of cold aqueous NaHCO solution (IN). The basic aqueous solution so obtained was extracted five times with 50 ml. of chloroform. The chloroform extract was dried and evaporated under reduced pressure to give an amorphous solid. This solid was dissolved in dilute acetic acid, filtered (to remove a small amount of insoluble material) and the filtrate was extracted four times with 50 ml. of chloroform. The chloroform extract was dried and evaporated to dryness under reduced pressure to yield 6.0 g. (43%) of 2',3- isopropylidene adenosine-S-(N,N-dimethyl)carboxamide. The crude amide (m.p. l06-1IOC) was dis solved in 100 ml. of 1N HCL and kept at 6070 for 45 minutes. The solution was then cooled, basified with NaHCO and evaporated to dryness under reduced pressure.

The residue, upon recrystallization three times from absolute ethanol, gave 3.0 g. (23%) of adenosine-5'- (N,N-dimethyl)carboxamide as a monohydrate; m.p. 190-l9l; [011 if l 7:0.3(c. 3 in IN l-lCl). Elemental analysis and nuclear magnetic resonance data 7 confirmed the identity of the compound.

EXAMPLE 5 Adenosine-S'-[(N-ethyU-Carboxamide] Freshly prepared 2,3'-isopropylidene adenosine-5'- carboxylic acid chloride (prepared from 6.4 g. of2,3- isopropylidene-S-carboxylic acid) was stirred with excess of dry liquid ethyl amine at to -35. The clear redorange solution was allowed to warm up to room temperature and kept at this temperature for l5 hours. At the end of this period the excess of ethyl amine had evaporated off. The residue was triturated with cold aqueous NaHCO; solution. The white precipitate was filtered off and washed with a small amount of cold water to yield 3.l g. (44.5%) of crude 2',3'- isopropylidene-5'-[(N-ethyl)-carboxamide] 225-227. R 0.72 (silica gel) system: n.BuOH:- H O:NH,OH (86zl4z5). The above amide was mixed with 80 ml. of l N HCl and kept at for 45 minutes. The acidic solution was then cooled and basified with NaHCO The mixture was then evaporated to dryness under reduced pressure, and the residue recrystallized twice from absolute ethanol and finally from water. The white crystalline product was dried in vacuo for 2 days over P 0 at -78 to give 0.9 g. (32 71) of adenosine-5-[(N-ethyl)carboxamide] which melted slowly at l36-l72 and solidified again at l48-150 and finally melted at 246-247 (sharp). [c11 l63 (c, 0.92 in l HCl); R 0.51 (silica gel). System: n- BuOH:H O:NH OH (86:l4:05); NMR (deuterated DMSO) peaks (in ppm) at 5.6 (2OH, 3'0H), 7.4 (EC-NR5); 8.8 (CONH 3.2 (C HQCFIQI Elemental analysis and NMR data confirmed the identity of the compound.

The following compounds are prepared according to the method of Example 4, substituting the appropriate amine for diethylamine.

O l 726 Rccrystn. D R Example R R Hp'C. Solvent otation C/INHCI 6 4.2 3 l-l 2 06-247 H 0 461310.5 0 0.92 0.51 7 -C H -O-C li ii 107-110 EtOfl -7.4to.9 0.54 0.44 a 41113; a 137-141 EtOH -912.2 0.223 0.53

.9 -(ca ca a 104-106 mm -a.9t1.s 0.334 0.56 10 -CH -CH-CH ll 223-224 EtOll -13 5T1 4 0- 369 0 50 11 -ca -c ca a -137 econ -27.s1'o.s 0.44 0.44 12 a 249-250 mm -6.8T0.8 0.584 0.47

13 ma -Q ll 130-133 11 0 -6.3f1.5' 0.315 0.55 14 (CH C1! It 125 molt-Acetone 15 -(CH CH ll 220-222 MeOH-Acetono- 2 Ether ,ca ca 16 -ca 11 a MeOH-EtOEt -1.61'0.a' 0.63

Cll CH3 17 -ca cooc: a a -170 Ac otono- -3. 7111.23 2.16

Ether ano sharp melting point b-TLC was done on Eastman 6060 Silica Gel Chromagram Sheet: with Fluorescent indicator. Solvent System used was: g-BuOl-hNHaOWHzO-Bfizhlh Examples Conld. R,(1) Empirical Formulae and Microanalysis Examples Contd. Empirical Formulae and Microanalysis Found. CHSHZIINNOJ Calcd. Found. I4 21 7 -1 Calcd. Found. CHHIHNHO-X Calcd. Found. m ln u b( 2o 24 u |KZ C 17 zo u u Calcd 50 Found. C. 50.

Examples Contd. R,{ 1) Empirical Formulae and Microanalysis Found. C, 33 0.66

l. R; values are obtained from the TLC. Unless otherwise specified, solvent system used was: nBuOHzN- H OH:H- O: 86:5:14. All compounds had a single spot in the TLC.

2. The total of the percentage composition of all the elements (C. H,N & 0) determined by the analyst was only or less. The compounds had a single 42 11 R H 0.137 -CH2CH-CH2 H. H 50 1 n n 1.23

-CH -(1-CH H H 55 (:H -ClliCH-CH H H 75 4 acecyl acetyl t 1.3

R is H in each of the above compounds NH The compounds of this invention can be formulated into various pharmaceutically acceptable dosage forms N I such as tablets, capsules, pills and the like for immediate or sustained releases by combining the active comk 1 pound with suitable pharmaceutically acceptable carri- O N N ers or diluents according to methods well-known in the 1 art. Such dosage forms may automatically includes ex- 40 cipients. binders, fillers, flavoring and sweetening 0 agents and other therapeutically inert ingredients nec- R2 essary in the formation of the desired preparation.

Preparations for parenteral administration include sterile, aqueous or non-aqueous solutions. suspensions OR OR or emulsions which are well-known in the art. 3 4

We claim: 1. A method of relieving inflammation and its conhe ein commitant symptoms of paint swelling and tenderness R is hydrogen; R and R are hydrogen with the proviin a mammalian patent comprising administering to sion that when R is cyclopropyl, R and R are hydrosaid patient a therapeutically effective amount of a gen or acetyl. compound of the formula 

1. A METHOD OF RELIEVING INFLAMMATION AND ITS CONCOMMITANT SYMPTONS OF PAIN, SWELLING AND TENDERNESS IN A MAMMALIAN PATENT COMPRISING ADMINISTERING TO SAID PATIENT A THERAPEUTICALLY EFFECTIVE AMOUNT OF A COMPOUND OF THE FORMULA 